At least 38 dead in fire at migrant center in Mexico near U.S. border

At least 38 people were killed as a fire broke out at a migration center along the U.S.-Mexico border, according to officials.

Authorities on Tuesday believe the fire was caused by a protest initiated by some of the migrants detained at the center "after, we think, they found out they’d be deported,” Mexican President Andrés Manuel López Obrador said.

Based on initial reports, migrants put small mattresses at the door of the shelter and set them on fire "as a form of protest," López Obrador said at a news conference Tuesday morning. "They didn’t imagine this would cause this misfortune."

Anthony Gonzalez, a Venezuelan migrant who was held at the facility last week after U.S. authorities sent him back to Mexico, told Noticias Telemundo he finds it hard to believe migrants could have started the fire, because they are held behind padlocked doors and “they take everything from you before entering.”

“That’s like a jail,” Gonzalez said in Spanish.

The fire began after 9 p.m. Monday at the migration center run by the National Migration Institute in Ciudad Juárez, the agency said in a statement. The migrants at the facility had been detained by authorities.

The country's National Migration Institute lowered the death toll on Tuesday evening from 40 to 38 following visits to hospitals across the city where victims had been taken and releasing the names of the fatal victims.

The institute did not immediately reveal the cause of the fire. It said that it “strongly rejects the acts that led to this tragedy,” without elaborating on what they may have been.

Dozens more people were injured, 29 of whom were taken to four hospitals in "delicate-serious condition," the agency said, adding that 68 men from Central America and South America — mainly Venezuela — were being held in the facility at the time.

Guatemala’s General Directorate of Migration confirmed that 28 of the dead were Guatemalans.

According to the country’s prosecutor general, which has opened an investigation, 13 Hondurans, 12 Salvadorans, 12 Venezuelans, a Colombian and an Ecuadorian were among the 68 people affected by the blaze.

Consular teams were also being engaged to further identify the dead, officials said.

‘Smoke started coming out of everywhere’

Images showed rows of bodies laid out under silver sheets as rescue teams, firefighters and police responded.

Amid the chaos, a Venezuelan migrant, Viangly Infante, had been desperately looking for her husband, Eduard Caraballo, 27.

Caraballo was one of many migrants who had been picked up by Mexican authorities Monday and detained at the National Migration Institute center, Infante said.

“I was here since 1 in the afternoon waiting for the father of my children, and when 10 p.m. rolled around, smoke started coming out from everywhere,” she told Reuters.

Her husband survived, Infante said, by dousing himself in water and pressing against a door.

Francisco Garduño Yañez, the commissioner of the National Migration Institute, was visiting the hospitals where the injured migrants were taken “to check on their health conditions,” the agency said in a tweet.

The agency also said immigration authorities “will provide Visitor Cards for Humanitarian Reasons to the injured and will cover the medical requirements for a speedy recovery.” Migrants who are seeking refugee status or were victims of crimes in Mexico can be eligible for the cards.

Betty Camargo, the state programs director at the Border Network for Human Rights, a human rights advocacy and immigration reform organization in the U.S.-Mexico border, said she has been speaking to migrants who witnessed the fire at the center and the events that preceded it.

Authorities inside the center told some of the detained migrants they were being deported, even though many of them had temporary work permits that are renewed every month, Camargo said. The migrants said they were told such permits would be taken away from them, she added.

Fernando García, executive director of the Border Network for Human Rights, said such migration centers “should not be detention centers."

Most migration centers run by the National Migration Institute are meant be processing centers and "a centro de alojamiento" (shelter) meant for short stays for migrants in transit.

That has prompted the organization to call for an investigation into the fire.

The facility, in Chihuahua state, is on the Mexico side of a bridge that connects Ciudad Juárez and El Paso, Texas.

Ciudad Juárez is a major crossing point for migrants trying to make the journey across the border to the U.S. Its shelters are full of migrants waiting for opportunities to cross or who are waiting out the asylum process.

In recent years, as Mexico has stepped up efforts to stem the flow of migration to the U.S. border under pressure from Washington, its National Immigration Institute has struggled with overcrowding in its facilities.

This article was originally published on NBCNews.com